Consumption of Ultra-Processed Foods and Cancer Risk

This study was the first to evaluate the association between the consumption of ultra-processed food products and the incidence of cancer, specifically breast, prostate and colorectal cancer. The authors calculated the percentage of the participant’s diet that was comprised of ultra-processed foods. They then compare the risk of cancer between the highest 25% consumption to the lowest 25% consumption. The top 25% had a diet of 32% from ultra-processed foods. The bottom 25% had a diet of 8% from ultra-processed foods. This resulted in the top 25% having a 23% increased risk of cancer compared to the bottom 25%. The greatest risk cancer was breast cancer. For post-menopausal in the highest 25% there was a 38% increased risk of breast cancer. For pre-menopausal in the highest 25% there was a 27% increased risk of breast cancer. “These results suggest that the rapidly increasing consumption of ultra-processed foods may drive an increasing burden of cancer in the next decades.”

Abstract:

104 980 participants aged at least 18 years (median age 42.8 years) from the French NutriNet-Santé cohort (2009-17). Dietary intakes were collected using repeated 24 hour dietary records, designed to register participants’ usual consumption for 3300 different food items. These were categorised according to their degree of processing by the NOVA classification. Ultra-processed food intake was associated with higher overall cancer risk (n=2228 cases; hazard ratio for a 10% increment in the proportion of ultra-processed food in the diet 1.12 (95% confidence interval 1.06 to 1.18); P for trend<0.001) and breast cancer risk (n=739 cases; hazard ratio 1.11 (1.02 to 1.22); P for trend=0.02). These results remained statistically significant after adjustment for several markers of the nutritional quality of the diet (lipid, sodium, and carbohydrate intakes and/or a Western pattern derived by principal component analysis). In this large prospective study, a 10% increase in the proportion of ultra-processed foods in the diet was associated with a significant increase of greater than 10% in risks of overall and breast cancer. Further studies are needed to better understand the relative effect of the various dimensions of processing (nutritional composition, food additives, contact materials, and neoformed contaminants) in these associations.

These authors also note:

Cancer represents a major worldwide burden, with about 14.1 million new cases diagnosed yearly.

The World Cancer Research Fund/American Institute for Cancer Research indicates that about a third of the most common cancers could be avoided by changing lifestyle and dietary habits in developed countries.

The most important modifiable risk factors in the primary prevention ofcancer are:
• Avoidance of Tobacco
• Reduction in Alcohol Intake
• Having a balanced and diversified diet

“During the past decades, diets in many countries have shifted towards a dramatic increase in consumption of ultra-processed foods.”

Surveys in Europe, the US, Canada, New Zealand, and Brazil indicate that consumption of ultra-processed food products contribute to between 25% and
50% of total daily energy intake.
• Ultra-processed foods have undergone multiple physical, biological, and/or
chemical processes.
• Ultra-processed foods are conceived to be microbiologically safe, convenient,
highly palatable, and affordable.

“Several characteristics of ultra-processed foods may be involved in causing disease, particularly cancer.”

These foods have “neoformed contaminants, some of which have carcinogenic properties (such as acrylamide, heterocyclic amines, and polycyclic aromatic hydrocarbons) and are present in heat treated processed food products as a result of the Maillard [glycation] reaction.”

“The packaging of ultra-processed foods may contain some materials in contact with food for which carcinogenic and endocrine disruptor properties have been postulated, such as bisphenol A.”

“Ultra-processed foods contain authorized, but controversial, food additives such as sodium nitrite in processed meat or titanium dioxide (white food pigment), for which carcinogenicity has been suggested in animal or cellular models.”

“The association with overall cancer risk was statistically significant in all strata of the population investigated.”

Ultra-processed foods have a “higher glycemic response and a lower satiety effect.”

The wide range of additives contained in ultra-processed foods may be cumulative: more than 250 different additives are authorized for addition to food products in Europe and the US.

Long-term exposure to aspartame or other artificial sweeteners may promote cancer.

Nitrosamines in meats, including sodium nitrite, may cause colorectal cancer.

“Rapidly increasing consumption of ultra-processed foods may drive an increasing burden of cancer and other non-communicable diseases.”

“These results suggest that the rapidly increasing consumption of ultraprocessed foods may drive an increasing burden of cancer in the next decades.”